Door closer with back check



Sept. 19, 1961 M. M. CHECK DooR CLOSER WITH BACK CHECK Filed May 3, 1960 A r Tof/v6? United States Patent@ 3,000,043 DOOR CLOSER WITH BACK CHECK Mathias M. Check, Stratford, Pa., assiguor to The Yale and Towne Manufacturing Company, Stamford, Conn., a corporation of Connecticut Filed May 3, 1960, Ser. No. 26,604 4 Claims. (Cl. 16-64) This invention relates to a door check and closer of the piston type in which the piston is provided with a fairly large port through which the checking uid may freely pass from one side of the piston to the other during movement of the piston in a door-opening direction so that there is little resistance to opening of the door.

More particularly, the invention relates to a back check arrangement for such a closer whereby the speed of the piston in the door-opening direction is checked or retarded just before the piston reaches its limit of movement in the door-opening direction.

The advantage of a back check arrangement in reducing the shock imposed on the closer and the mounting means when a door is rapidly opened to its extreme position is well-known, and various back check arrangements have heretofore been proposed. Such arrangements, however, are quite complicated and costly and are not adapted to be used on conventional closers without substantial modification and alteration of such closers.

The present invention provides a very simple back check arrangement which may be quickly and easily applied to conventional types of closers without substantial modications or alteration of the closers. The invention, therefore, permits the same basic closer to be used with or without a back check arrangement, thus reducing the number of parts that must be manufactured and stocked by the closer manufacturer. Furthermore, a closer without a back check arrangement may be quickly and easily converted to one having a back check A arrangement at a later date if such is desired.

In accordance with the invention, the back check arrangement includes a closure member which is yieldingly supported in the path of movement of the piston and is adapted to be engaged by and moved with the piston to close the port through the piston during the final movement of the piston in the door-opening direction. Thus, during initial movement of the piston in the door-opening direction, the port through the piston remains open to permit the free flow of fluid from one side of the piston to the other so that there is little resistance to the opening of the door. However, during the nal movement of the piston the closure member closes the port through the piston to provide uid checking during the iinal movement of the piston so that the closer is not subjected to a sudden shock when the piston reaches its limit of movement in the door-opening direction.

As la. feature of the invention, the closure member is yieldingly supported on the end of a helical compression spring which bears against one end of the piston chamber of the closer and extends toward the piston. This compression spring is conveniently mounted Within the usual door-closing spring so that the closure member is supported and guided by the door-closing spring. The closure member and its spring support may therefore be readily mounted in the closure through the same opening as that used for mounting the usual door-closing spring.

The invention and its advantages having been broadly described, a more detailed description of one embodiment of the invention is given hereafter by reference to the accompanying drawing, wherein:

FIG. l is a sectional view of a door check and closer incorporating the back check arrangement of the invention, and showing the piston in a position corresponding to a closed position of the door,

FIG. 2 is a sectional view similar to that shown in FIG. l but showing the piston moved to a position in which the piston has just engaged the closure member of the hack check arrangement so that a port through the piston is closed to provide uid checking of the piston during its nal movement in the door-opening direction, and

FIG. 3 is a sectional view taken on the line 3-3 of FIG. 2 to show a at portion provided on the piston to provide controlled leakage of uid past the piston during back checking of the piston.

Referring to the drawing, and in particular to FIGS. 1 and 2, the back check arrangement of the invention is shown applied to a door check and closer of a conventional type which includes a body or housing 10 providing a iluid-lled piston chamber 11 in which a piston 12 is slidably disposed. The ends of the piston chamber 11 are conveniently closed by threaded end caps 13 and 14 which are screwed into the ends of the chamber.

As is well-known to those skilled in the art, the housing 10 is secured to the face of a door to be controlled adjacent the top of the door by suitable fastening means, and opening and closing movement of the door is translated into sliding movement of the piston 12 by hinged arms (not shown) which are connected at one end to the frame of the door and are connected at the other end to a vertical shaft 15 which is suitably journaled in the housing 10 and carries a pinion 16 which meshes with rack teeth 17 formed on a skirt portion 1S of the piston 12. When the door is moved toward a closed position the pinion 16 rotates in a counter-clockwise direction and the piston 17 moves toward the right to the position shown in FIG. l. When the door is moved toward an open position the pinion 16 rotates in a clockwise direction and the pister 12 moves toward the left as shown in FIG. 2.

During movement of the piston 12 to the right as theF door is opened, a helical compression spring 19, inter posed between the head 20 of the piston 12 and the end cap 13, is compressed so that when the door is released the spring 19 will move the piston to the right thereby `closing the door.

During a major portion of the movement of the piston 12 to the left during opening of the door, uid in the chamber 11 m-ay freely pass from the left side of the piston 12 to the right side of the piston through a relatively large port 21 formed through the head 20 of the piston 12. Thus, during the major portion of the opening movement of the door there is little fluid resistance to the movement of the piston 12 so that relatively little eiort is necessary to open the door.

When, however, the door is released, and the oompressed spring 19 moves the piston 12 to the right to close the door, a ball check 22 closes the port 21 thereby preventing the ow of uid through the port 21 from the right-hand side of the piston 12 to the left-hand side. Thus, in order for the uid to pass from the right-hand side of thel piston to the left-hand side of the piston, the uid in the chamber 11 on the right-hand side of the piston 12 must flow through ports 23 and 24 formed through the wall of the chamber 11, through a regulating valve 25, a bore 26, a ball check valve 27 yand ports 28 and 29 provided at the opposite end of the chamber from the ports 23 and 24, and into the chamber 11 on the left-hand side of the piston. The regulating valve 25 allows the rate of ow of the fluid from the right-hand side of the piston to the left-hand side of the piston to be adjusted to check the speed of the piston 12 in its movement toward the right to prevent slamming of the door.

The particular regulating valve disclosed is of the general type and functions in a similar manner to that shown in U.S. Patent 1,151,339, and is conveniently mounted in one end of the bore 26. The opposite end of the bore 26 is closed by a suitable plug 30. The regulating valve 2S includes a valve sleeve 31 which is received in the end of the bore 26 and has ports 32 and 33 which align Patented Sept. 19, 1961.

with ports 23 and 24. A regulating plunger or screw 34 is received in the sleeve 31 and is threaded through va bushing 35 so that it may he adjusted relatively to the sleeve 31 by rotation thereof in the bushing 3 5. 'I he bushing 35 is threaded into the end of the bore 2,@ The plunger 34 has 'an endy portion 36` oi reduced. diameter to provide clearance 37 with the sleeve 31. The end of; thelreduced portion 36 extends through an opening 38 inthe end cf the sleeve 51, and, has tapered metering surface or groove 39 forrnedi therein,- Afseeond rnetering surface 4l) is formed on the plunger 34 at the juncture of the reduced portion 36 and the remainder of the plunger. The rate of flow ofiluid from the ports 23 and' 24 through the valve may be adjusted byV varying the degree that the metering surface 39 overlaps the inner edge of the opening 3S in the sleeve 31, and the degree 'that the metering surface 40 overlaps the port 32. A gasket 41 interposed between the end ot the sleeve 31. and the bushing 35 prevents leakage. of.` fluid gaat plunger 34. Y'

i Asfthepiston 12 moves toward the right, the port; 2.3 is gradually closed by a tapered surface 42 formed on the, cuter periphery of the head 2,0 of the Pisten 12, se that. the fluid checking is gradually increased: When, however, the tapered surface e2; passes. the port.v 23. the, checlg ing eiect is decreased. as the duid. may flow irons the. right-hand side of the gisten,A through the port 24, port 33 surface 4e, clearance 375, port. 3?. port 2.3; Past the pinion 16;', and in to the4 here 2l6- T hisA ensures sumcient force to provide proper latehing of.A the door during final, unevernent` ot thedoer.

It will be appreciated.v that, as so far described the ehecls and closer. is 'af completely operable. unit which may he. used without modification. when bucle cheehing isY not necessary or desired. In. accordance. with the invention, this conventional closer may be quiclsly and easily convetted( to a closer incorporating back chee '-g by in; serting a smaller and shorter helical compression spring 43 through the usual. door-closing spring 9., andfsun`v porting a closure nieniber 4.4 on the free end of. the springrin alignment with port 21 through the piston head 20- The spring 43 is easily insertedat any tine hy removal of the end cap 13. rThe length of the spring 43 is selected so that the closure member 44 is spaced a predetermined distance from the port 21 when the piston 12 is in the extreme position to the right as shown in FIG- 1. Preferably, this predetermined distance is equal to the distance the piston 12 must travel when the door is opened about seventy-tive percent. Thus, when the door is moved from a closed position, fluid may ow freely through the port 21 from the left side of the piston 12 to the right side until the door has been opened approximately seventy-uve percent. At this time the closure member 44 is engaged by the piston 1,2 and the port 21 is closed by the closure member 44, as shown in FIG. 2t so that the iiuid can no longerow through the port 2,1 from the left side of the piston to the right Side#V The uid must, therefore, owat a much slower rate through a. passage d5, best shown in FIG 3, tormed between the piston 12 and the chamber wall by a fiat portion 46 provided on the periphery of the Skirt 18 of the piston 12. Thus, the final movement of the piston 12- in the door opening direction toward the left; as indicated by the broken lines in FWGY. 2, is checkedV or retarded so' that there is no sudden shock, when the piston 12 reaches its limit oi rnovernen-t.

The passage e5 formed by the flat Portion 46 is of course only one way of providing a restricted passage,Y

fer he nur@ to flow from the leringen sise or me piston to the right-hand side ofy the pistonV during theY back checking of the piston. Small passages fof the same purposecan be provided at other points in the closer. For example, a small passageway could be provided through the closure rnenrber 44, er through the checls. valve 27. v

The closure member 44 preferably has an enlarged cylindrical body portion 47 so that the closure member is guided by the inner surface of the convolutions of the closing spring 19. The1 closurje member 44 is conveniently supported on the end of the spring 43, by means et au integral shanh portion 48., which extendsv intothe end of the spring 4,3. The oppositeA end of the closure member 44 is provided with a pilot portion 4 9 having a tapered end which is adapted to engage in and center the closure member 44v relatively to th port 21. A rubber Washer or gasket. it! surrounds the pilot portion 49l and engages the surface of the head of the. piston 2.0 surrounding the port 2,1. to ensure Proper closing of the. gort The opposite end. et the spring. 4 trein the closureV niernher 44 is held. centered. on a ein. 5.1V which extends. from au annuler disc 5.2 whi his; held,- against the end cap 1 3; hy the pressure or the ,oser storing 1.9..`

Front the preceding description it can bey seen that there is, provided a nevel heele ches ing arrangement which `may hequiclily all@ easily appliedto a conventional door check and closer with very little modication or altera.-` tion of the closer.V 'I-hus,V the invention permits the same closer and checlgto bel offered with or without back checking, depending on the particular use to which the closer is tobe put, and also permits back checking to be addedytoa closer at aV later date if' such isV desired.

While a preferred form of the invention has been shown and described, it will be appreciated that this is for the purpose of illustration, and that changes and modifications may be made therein without, departing from the spirit and scope of the invention.

I now claim:

1. A door closerv comprising, a housing having a duid lled chamber therein, a piston movable in. said chamber, a port through said piston whereby said fluid may pass freely from one side oi the, piston to the other side when said piston is moved in one direction in said chamber, a check valve for closing said port tol prevent the free flow of fluid. through said port when said piston is moved in the other direction in said chamber whereby to check the movement of said piston in said other direction, a helical compression spring extending from one end of said chamber toward said one side of said piston, `and a closureV member supported. on the free end of said spring in alignment wit-h said port and spaced a predetermined distance f rom said port Whensaid pistonV displaced to an extreme position in said other direction whereby said closure member will be engaged by said piston and closeA said portto provide fluid checking of the final movement of said piston in saidone direction.

2. A door closer comprising, ahousing having a fluid filled ehambertherein, apiston'movable inisaid chamber, a port through said piston whereby said iluid may pass freely from one side of the piston to the other side when said piston is moved in one Adirection in said chamber, a check valve for closing said port to prevent the free flow of fluid through said Port when said piston is moved in the other direction in 'said chambe; whereby to check the movement of said piston in said' other direction, a iirst helical compression spring extending between one end of said chamber and said one side of said piston for moving said piston in saidother direction, a second shorter helical compression spring ertendingy from said one end of said chamber through the center of said first helical compression spring, and a closure member supported on the free end of said second spring in alignment with said port and spaced a predetermined distanceA from said port when said piston is displaced to an extreme position in said other direction, whereby said closure member will be engaged by said Apiston and closel said port to provide uid checking of said piston during the inalV movement of said piston in said one direction. t

3. A door closer comprising,l a housing having a fluid lled chamber therein, a piston movable in said chamber, a port through said Piston whereby said fluid may pass freely from one side of the piston to the other side when said piston is moved in one direction in said chamber, a check valve for closing said port to prevent the free ow of uid through said port when said piston is moved in the other direction in said chamber whereby to check the movement of said piston in said other direction, a rst helical compression spring extending between one end of said chamber and said one side of said piston for moving said piston in said other direction, a second shorter helical compression spring extending from said one end of said chamber through the center of said first helical compression spring, and a closure member supported on the free end of said second spring in alignment with said port and spaced a predetermined distance from said port when said piston is displaced to an extreme position in said other direction, whereby said closure member will be engaged by said piston and close said port to provide fluid checking of said piston during the nal movement of said piston in said one direction, said closure member having a cylindrical body portion guided by the inner surface of said irst helical compression spring.

4. A door closer adapted to control opening and closing of a door and comprising, a housing having a fluid lilled chamber therein, a piston movable in said chamber, a port through said piston whereby said uid may pass freely from one side of the piston to the other side when said piston is moved in one direction in said chamber corresponding to opening movement of the door which the closer is adapted to control, a check valve for closing said port to prevent the free ow of uid through said port when said piston is moved in a reverse direction in said chamber corresponding to closing movement of the door whereby to check the movement of said piston in said reverse direction and the closing movement of the door, a closure member of a size and shape to close said port in said piston, said closure member being disposed on that one side of said piston toward which the piston moves during opening movement of the door, and means yield# ingly supporting said closure member in said chamber on said one side of said piston in position to engage said port while spaced from said port when said piston is displaced to an extreme position in said other direction with the said door closed, whereby said piston may move in said one direction toward said closure member during opening movement of the door with Huid flowing freely through said port and thereafter engage and move said closure member therewith so that said port is closed by said closure member to provide uid checking of said piston during nal movement of said piston in said one direction so as to check the final opening movement of the door.

References Cited in the tile of this patent UNITED STATES PATENTS 1,455,691 West May 15, 1923 

